Art of cementing low-carbon iron.



UNTTED TATES PATENT @FFTQE.

H'UGH RODMAN, OF PITTSBUBG, PENNSYLVANIA.

ART or CEMENTING LOW-CARBON mom.

No Drawing.

To all whom it may concern:

Be it known that I, HUGH RonMAN, a citizen of the United States, and a resident. of Pittsburg, in the countyof Allegheny and State of Pennsylvania, have madea new and useful Invention in the Art of Cementing Low-Carbon Iron, of which the following is a specification.

This invention relates to the art of cementing low carbon iron and more particularly to cementing material for use. in said art.

The necessity of using a non-shrinkable cementing material is Well understood by those skilled in this art. Metal parts to be cemented or case-hardened require firm support in their heated state to revent Warping and accidental contact an for that reason non-shrinkable cementing material, such as bone, is ordinarily used.

I have found that cementing materials,

which are subject to harmful shrinkage in use, may, prior to use, be heated so as to bring about maximum or nearly maximum. shrinkage without mater ally reducing their cementing power. Coke granules or dust mixed with, say 50% of powdered soda ash will shrink about 3572411 volume, due principally to the absorption by the coke of the fused soda-ash or the'resultant oxid and partially tothe reducing action of the coke upon the soda-ash. Commercial charcoal mixed with 25% of powdered soda-ash shrinks about- 85%, due partly to the shrinkage of the charcoal and partly to the reduction and absorotion of the sod-a-a sl1. Lignite and peat shrink from 40% to 80%, de-v pending upon the moisture content and chemical constituents. If heated with energizing substanc'es easily fused or reduced, such as soda-ash, the shrinkage is even greater. I have found that by pre-heating these materials, preferably in closed recep- Specification of Letters Patent.

Patented Feb. 1916 Application filed may 15, 1909. Serial No. 496,270.

tacles or'pots, the maximum shrinkage can be brought about without materially reducng their cementing powers thereby increasing their usefulness and, in fact, rendering useful some which Without such treatment.

while with a mixture of coke and soda-ash.

it is necessary to reachvthe fusing or reducing temperature of the soda-ash, roughly about 1500 Fahrenheit and on account of these variations, I do not wish to limit this invention to any particular time or temperature, but consider that the time or temperature, or combination'of the two, whichwill bring about the desired shrinkage without materially reducing the cementing power of the mixture will fall within thescope of this invention.

Having thus described my invention, what I claim isi 1. The method of preparing coal of the soft, non-coking variety for use as cementing material'which consists in shrinking the same bythe application of heat.

2. The method of preparing peat for use as cementing material which consists in shrinking the same by the application of heat.

In testimony whereof, I have hereunto subscribed my name this 12th day of May,

HUGH RODMAN.

Witnesses:

C. W. MCGHE GEO. C. WALKER. 

